The following U.S. Patents and Applications provide background information and are incorporated herein by reference in entirety.
U.S. Pat. No. 4,872,857, which is hereby incorporated herein by reference in entirety, discloses a system for optimizing the operation of a marine drive unit the position of which is independently variable by separately operable trim and vertical lift systems. The system includes trim and lift position sensors, the output signals of which are stored by the control system, such that the trim and lift positions for any previously established drive unit operating mode may be subsequently used to automatically return the drive unit to that particular position. Automatic repositioning is accomplished by manual selection of one of several operating modes, such as trolling, acceleration, or cruising. Automatic movement to a pre-established uppermost trailering position may also be provided. The system includes appropriate controls based on sensed boat speed (MPH) or engine speed (RPM) to preclude return to one of the pre-established operating positions when such return would be impractical or potentially hazardous.
U.S. Pat. No. 6,234,853, which is hereby incorporated herein by reference in entirety, discloses a docking system that utilizes the marine propulsion unit of a marine vessel, under the control of an engine control unit that receives command signals from a joystick or push button device, to respond to a maneuver command from the marine operator. The docking system does not require additional propulsion devices other than those normally used to operate the marine vessel under normal conditions. The docking or maneuvering system uses two marine propulsion units to respond to an operator's command signal and allows the operator to select forward or reverse commands in combination with clockwise or counterclockwise rotational commands either in combination with each other or alone.
U.S. Pat. No. 6,322,404, incorporated by reference herein, discloses a Hall effect rotational position sensor is mounted on a pivotable member of a marine propulsion system and a rotatable portion of the rotational position sensor is attached to a drive structure of the marine propulsion system. Relative movement between the pivotable member, such as a gimbal ring, and the drive structure, such as the outboard drive portion of the marine propulsion system, cause relative movement between the rotatable and stationary portions of the rotational position sensor. As a result, signals can be provided which are representative of the angular position between the drive structure and the pivotable member.
U.S. Pat. No. 7,267,068, which is hereby incorporated herein by reference in entirety, discloses a marine vessel maneuvered by independently rotating first and second marine propulsion devices about their respective steering axes in response to commands received from a manually operable control device, such as a joystick. The marine propulsion devices are aligned with their thrust vectors intersecting at a point on a centerline of the marine vessel and, when no rotational movement is commanded, at the center of gravity of the marine vessel. Internal combustion engines are provided to drive the marine propulsion devices. The steering axes of the two marine propulsion devices are generally vertical and parallel to each other. The two steering axes extend through a bottom surface of the hull of the marine vessel.
U.S. Pat. No. 7,416,456, incorporated by reference herein, discloses an automatic trim control system changes the trim angle of a marine propulsion device as a function of the speed of the marine vessel relative to the water in which it is operated. The changing of the trim angle occurs between first and second speed magnitudes which operate as minimum and maximum speed thresholds.
U.S. Pat. No. 7,467,595, which is hereby incorporated herein by reference in entirety, discloses a method for controlling the movement of a marine vessel that rotates one of a pair of marine propulsion devices and controls the thrust magnitudes of two marine propulsion devices. A joystick is provided to allow the operator of the marine vessel to select port-starboard, forward-reverse, and rotational direction commands that are interpreted by a controller which then changes the angular position of at least one of a pair of marine propulsion devices relative to its steering axis.
U.S. Pat. No. 8,622,777, which is hereby incorporated herein by reference in entirety, discloses a system for maneuvering a marine vessel comprises an input device for requesting a reverse thrust of a marine propulsion device and a control circuit that, based upon the request for the reverse thrust from the input device, controls movement of the marine propulsion device into a trim position wherein the marine propulsion device provides a reverse thrust that is not impeded by a hull of the marine vessel. Optionally, the input device can comprise a joystick.
U.S. Pat. No. 9,434,460, which is hereby incorporated herein by reference in entirety, discloses systems for maneuvering a marine vessel including an input device for requesting lateral movement of the marine vessel with respect to the longitudinal axis and a plurality of propulsion devices including at least a port propulsion device, a starboard propulsion device and an intermediate propulsion device disposed between the port and starboard propulsion devices. A control circuit controls orientation of the port and starboard propulsion devices inwardly towards a common point on the marine vessel, and upon a request for lateral movement of from the input device, operates one of the port and starboard propulsion devices in forward gear, operates the other of the port and starboard propulsion devices in reverse gear, and operates the intermediate propulsion device in reverse gear.